Today's elevator systems are equipped with a safety circuit. This safety system is composed of a plurality of switching contacts that are connected in series and belong to different safety elements for monitoring the shaft, the door and the rope. Opening one of these switching contacts results in the interruption of the entire safety circuit. This, in turn, causes interruption of the power supply to the main drive, engaging of the brake and therefore adopting a safe idle state of the elevator system. In order to integrate all safety elements into the safety circuit, the safety circuit needs to be routed through the entire shaft and also via the traveling cable to the car. As a result of this routing, a line harness of the safety circuit routed to the safety elements and a line harness of the safety circuit routed back from the safety elements are often close together. Thus, a cross-circuit between the line harness routed to the safety elements and the one routed back cannot be excluded. However, a cross-circuit of these line harness results in that the switching contacts in the line harness therebetween have to be bridged and, consequently, their switching state can no longer be detected or is always considered as being closed. Previously, this could only be prevented by a reliable but also relatively complicated insulation.